USB: UHCI: add support for Intel's wakeup flags

This patch (as1396) adds code to uhci-hcd to support the
vendor-specific wakeup settings found in Intel's ICHx hardware.  A
couple of unnecessary memory barriers are removed.  And the root hub
isn't put back into the "suspended" state if power was lost during a
system sleep -- there's not much point in doing so because the root hub
will be resumed shortly.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/host/uhci-hcd.c

@@ -176,6 +176,8 @@ static void check_and_reset_hc(struct uhci_hcd *uhci)
  */
 static void configure_hc(struct uhci_hcd *uhci)
 {
+	struct pci_dev *pdev = to_pci_dev(uhci_dev(uhci));
+
 	/* Set the frame length to the default: 1 ms exactly */
 	outb(USBSOF_DEFAULT, uhci->io_addr + USBSOF);
 
@@ -191,8 +193,11 @@ static void configure_hc(struct uhci_hcd *uhci)
 	mb();
 
 	/* Enable PIRQ */
-	pci_write_config_word(to_pci_dev(uhci_dev(uhci)), USBLEGSUP,
-			USBLEGSUP_DEFAULT);
+	pci_write_config_word(pdev, USBLEGSUP, USBLEGSUP_DEFAULT);
+
+	/* Disable platform-specific non-PME# wakeup */
+	if (pdev->vendor == PCI_VENDOR_ID_INTEL)
+		pci_write_config_byte(pdev, USBRES_INTEL, 0);
 }
 
 
@@ -791,6 +796,7 @@ static int uhci_rh_resume(struct usb_hcd *hcd)
 static int uhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
 {
 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
+	struct pci_dev *pdev = to_pci_dev(uhci_dev(uhci));
 	int rc = 0;
 
 	dev_dbg(uhci_dev(uhci), "%s\n", __func__);
@@ -808,11 +814,15 @@ static int uhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
 	/* All PCI host controllers are required to disable IRQ generation
 	 * at the source, so we must turn off PIRQ.
 	 */
-	pci_write_config_word(to_pci_dev(uhci_dev(uhci)), USBLEGSUP, 0);
-	mb();
+	pci_write_config_word(pdev, USBLEGSUP, 0);
 	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
 
-	/* FIXME: Enable non-PME# remote wakeup? */
+	/* Enable platform-specific non-PME# wakeup */
+	if (do_wakeup) {
+		if (pdev->vendor == PCI_VENDOR_ID_INTEL)
+			pci_write_config_byte(pdev, USBRES_INTEL,
+					USBPORT1EN | USBPORT2EN);
+	}
 
 done_okay:
 	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
@@ -831,16 +841,13 @@ static int uhci_pci_resume(struct usb_hcd *hcd, bool hibernated)
 	 * even if the controller was dead.
 	 */
 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
-	mb();
 
 	spin_lock_irq(&uhci->lock);
 
 	/* Make sure resume from hibernation re-enumerates everything */
 	if (hibernated)
 		uhci_hc_died(uhci);
 
-	/* FIXME: Disable non-PME# remote wakeup? */
-
 	/* The firmware or a boot kernel may have changed the controller
 	 * settings during a system wakeup.  Check it and reconfigure
 	 * to avoid problems.
@@ -850,12 +857,9 @@ static int uhci_pci_resume(struct usb_hcd *hcd, bool hibernated)
 	/* If the controller was dead before, it's back alive now */
 	configure_hc(uhci);
 
-	if (uhci->rh_state == UHCI_RH_RESET) {
-
-		/* The controller had to be reset */
+	/* Tell the core if the controller had to be reset */
+	if (uhci->rh_state == UHCI_RH_RESET)
 		usb_root_hub_lost_power(hcd->self.root_hub);
-		suspend_rh(uhci, UHCI_RH_SUSPENDED);
-	}
 
 	spin_unlock_irq(&uhci->lock);
 

drivers/usb/host/uhci-hcd.h

@@ -67,12 +67,17 @@
 #define   USBPORTSC_RES3	0x4000	/* reserved, write zeroes */
 #define   USBPORTSC_RES4	0x8000	/* reserved, write zeroes */
 
-/* Legacy support register */
+/* PCI legacy support register */
 #define USBLEGSUP		0xc0
 #define   USBLEGSUP_DEFAULT	0x2000	/* only PIRQ enable set */
 #define   USBLEGSUP_RWC		0x8f00	/* the R/WC bits */
 #define   USBLEGSUP_RO		0x5040	/* R/O and reserved bits */
 
+/* PCI Intel-specific resume-enable register */
+#define USBRES_INTEL		0xc4
+#define   USBPORT1EN		0x01
+#define   USBPORT2EN		0x02
+
 #define UHCI_PTR_BITS		cpu_to_le32(0x000F)
 #define UHCI_PTR_TERM		cpu_to_le32(0x0001)
 #define UHCI_PTR_QH		cpu_to_le32(0x0002)